The Australian Transport Safety Bureau (ATSB) said the fully laden train, made up of four locomotives and 268 wagons, was travelling from the mining town of Newman to Port Hedland at 4:40am today, when the driver hopped out to inspect a wagon near Hester siding.

But the train took off from the siding before the driver could get back on board.

It travelled 90 kilometres in about 50 minutes, until it was derailed at a set of points about 120 kilometres from Port Hedland.

BHP said the derailment was implemented from its Integrated Remote Operations Centre in Perth.

The centre controls the company's Pilbara operations, including rail and port facilities.

The ATSB has begun an investigation into the incident, and a spokesman said it was hoping to interview the train driver as soon as possible.

BHP said no-one was injured in the derailment and it had suspended all train operations while the investigation is underway.

"We are working with the appropriate authorities to investigate the situation," a spokesperson said in a statement.